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raptor 350 smoke

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when I cold start my raptor it smokes extremely bad until it warms up. After it warms up it runs great and doesn't smoke at all . any ideas??

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Your valve seals are/going bad.  It doesn't affect the way it runs or reliability. It will eventually smoke full time like a poorly jetted 2 stroke with a fouled plug.  Fortunately it could take a while before that happens and even then it will still run fine.  You will need to keep an eye on your oil level.

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Your valve seals are/going bad.  It doesn't affect the way it runs or reliability. It will eventually smoke full time like a poorly jetted 2 stroke with a fouled plug.  Fortunately it could take a while before that happens and even then it will still run fine.  You will need to keep an eye on your oil level.

are valve seals hard to replace? this is my first 4 stroke so it's kind of new to me.

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Your valve seals are/going bad.  It doesn't affect the way it runs or reliability. It will eventually smoke full time like a poorly jetted 2 stroke with a fouled plug.  Fortunately it could take a while before that happens and even then it will still run fine.  You will need to keep an eye on your oil level.

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Valve seals are not hard to do but require quite a bit of experience with four stroke engines. To change valve seals you are basically doing the same amount of work as a top end (piston and ring). You must remove the cylinder head then will need a valve removal tool (they are inexpensive).  If you go to Babbitts or partzilla and select o.e.m. parts, then go to Yamaha, ATV parts and select your year and model you will see schematics of your engine. I used these to rebuild/repair things when I first started

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Valve seals are not hard to do but require quite a bit of experience with four stroke engines. To change valve seals you are basically doing the same amount of work as a top end (piston and ring). You must remove the cylinder head then will need a valve removal tool (they are inexpensive).  If you go to Babbitts or partzilla and select o.e.m. parts, then go to Yamaha, ATV parts and select your year and model you will see schematics of your engine. I used these to rebuild/repair things when I first started

thanks for the fast response. so it should be okay to keep riding until I find the time to do it? and while having the motor apart should I swap out the piston and ring also? the previous owner says he never changed it and neither did the owner before him

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Yes you can ride it without concern until you find time.  Just keep an eye on your oil level.  The smoke you see is oil leaking past the valve seals and burning when your quad fires.  It is harmless to the engine just annoying blue smoke.  

Frequent starts and warming up will help keep the seals from drying out more.  You are probably like me and don't get enough time to ride.

Changing piston and rings is completely up to you.  For the price of parts I say go for it.  There are so many manufacturers of piston kits these days driving the cost down. 

If you have any more questions or need help with the seal change please keep my email address: cmarsack@gmail.com.  You can send me photos with questions and I will do my best to walk you through it

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Yes you can ride it without concern until you find time.  Just keep an eye on your oil level.  The smoke you see is oil leaking past the valve seals and burning when your quad fires.  It is harmless to the engine just annoying blue smoke.  
Frequent starts and warming up will help keep the seals from drying out more.  You are probably like me and don't get enough time to ride.
Changing piston and rings is completely up to you.  For the price of parts I say go for it.  There are so many manufacturers of piston kits these days driving the cost down. 
If you have any more questions or need help with the seal change please keep my email address: cmarsack@gmail.com.  You can send me photos with questions and I will do my best to walk you through it

thank you for the help and I will definitely keep your email. my quad has a ticking noise that I'm kind of worried about that I want to look into soon so your help is appreciated

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